1. Field of the Invention
The present invention relates in general to a disc drive, which inputs and outputs signals by an earphone jack. In particular, the present invention relates to a disc drive having a signal switch device, driving the earphone jack to output audio signals or non-audio signals and input non-audio analog or digital signals.
2. Description of the Related Art
During the design of a disc drive, the manufacturer must trace the behavior of the disc drive under different conditions and simulate controlled status of the disc drive thereby. However, input testing or variable adjustment signals and output testing signals between the conventional disc drive and the testing machine are through a signal bus. Additional I/O ports are required to allow transmission of more testing signals. However, the additional I/O port increases the cost of the disc drive, countering current trends toward lower priced disc drive.
The object of the present invention is to provide a switching device connected to the earphone jack of a disc drive for switching the earphone jack to output both audio or non-audio signals, and input non-audio analog or digital signals.
To achieve the above-mentioned object, the present invention provides a disc drive that inputs and outputs signals by an earphone jack. The disc drive comprises a digital-to-analog converter, a signal switch device, and an earphone jack coupled to the signal switch device. When the signal switch device is coupled to the digital-to-analog converter, an audio signal is output from the disc drive through the earphone jack. When the signal switch device is disconnected from the signal switch device, a digital signal is input or output to/from the disc drive through the earphone jack.